It is a question that feels like it should have a straightforward answer: how many planets are there in our solar system? Since Pluto was relegated back down to dwarf planet status, almost everyone ...

Nearly a century after Pluto’s discovery, astronomers are still hunting for mysterious planets beyond Neptune - including a ...

Scientists may have discovered a dwarf planet far beyond Neptune — an unearthing that may disprove a longstanding theory about the possibility of a giant ninth planet. The dwarf planet's existence ...

Astronomers have discovered the earliest seeds of rocky planets forming in the gas around a baby sun-like star, providing a precious peek into the dawn of our own solar system. It’s an unprecedented ...

There’s a bit of a paradox about our galaxy: it’s both jam-packed with stars and cavernously empty. The Milky Way is crowded in the sense that it holds hundreds of billions of stars, as well as ...

CAPE CANAVERAL, Fla. — Astronomers have discovered the earliest seeds of rocky planets forming in the gas around a baby sun-like star, providing a precious peek into the dawn of our own solar system.